In SX Microcontrollers, SX/B Compiler and SX-Key Tool, cbmeeks wrote:

THANKS GUYS!

[quote="Michael Chadwick"]Just to jump in here, that is one fast SRAM chip, but I don't see in your plot macro or clear code where you cycle the write line.

To register the value, the write line has to go low for the specified 9 ns minimum, and *must* go high again to clock the data into the memory array.

....
MRC[/quote]

Man, I believe that is it!  I will try it this weekend...as soon as I remind Santa how to get to our house.  ;-D
But I get what you are saying.  I simply am not cycling correctly (or at all).  I *assumed* all you had to do was set the address you want, wait 15ns, send the data and that was it.  Looks like that is OK for reading but not writing.  All of my writing will be done during VBlank so super high speed shouldn't be a problem.  In fact, a 6502 will be responsible for the writing.  :-)


[quote="Bean (Hitt Consulting)"]I noticed that the current required is quite high.
Make sure you have proper caps as close as possible to the SRAM, and that your supply can handle the current needed.
Bean.[/quote]

Yup.  You can't see it in the pic but I have two caps within mm's of the powerpin.


[quote="Paul Baker"]What are you coupling to the video bus? Depending on what it is you can potentially eliminate the video bus by coupling it directly to the data bus (I use this trick frequently to reduce pin counts (might be handy since SX52 is discontinued)).[/quote]

You know, I actually thought about that.  Eventually, the SRAM will be shared with a 6502 and maybe even ANOTHER SX (for sprites).  But all that might be OK because only one would use the data/addr bus at any one point.

Plus, I am using an SX52 now because that is what I have.  The final product will use an SX48

cbmeeks

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